Problem in understanding self-inductance

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In summary, the conversation discusses the concept of induced electric fields and currents in conductors. The person is having trouble understanding why the electric field within the conductor must equal the induced electric field. It is explained that even though the total electric field within the coil is zero, there is still an electric field present that causes charges to move. Additionally, the person's understanding of the relationship between resistance and current is clarified, stating that in real life, the current is not infinite due to factors such as internal resistance in batteries.
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anachin6000
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In the photo I uploaded is the beginning of a study of inductors in circuits. They explain there why Ec must have the same value as En, but I don't get it:

If the total electric field inside the conductor is 0, then there should be no current in the conductor (because there is nothing which moves the charges). But the resistance is negligible (very close to 0), so the current should have an enormous value (because outside the coil we hare the generator that provides a emf). And also if the current inside the coil is 0, how is possible to have an induced emf.

Can someone explain what is wrong in my thinking (because I doubt that the book is wrong) and eventually explain this thing better?
 

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anachin6000 said:
If the total electric field inside the conductor is 0, then there should be no current in the conductor (because there is nothing which moves the charges).

did you not note the sentence after the Ec +En = zero ?
even tho the total electric field within the coil is zero, even tho Ec and En are individually non-zero. The fact that Ec is non-zero,
means there is an electric field present that will cause charges to move

anachin6000 said:
But the resistance is negligible (very close to 0), so the current should have an enormous value (because outside the coil we hare the generator that provides a emf).

Only in an idea condition would the current be infinite, in real life, as with the battery supply they have stated, the batteries have internal resistance
and this limits the maximum possible amplitude of the current flow

not sure of that helps ?

cheers
Dave
 
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1. What is self-inductance?

Self-inductance is a property of a circuit or an electromagnetic device that describes its ability to produce an induced electromotive force (EMF) in itself when the current changes. It is measured in units of Henrys (H).

2. What causes problems in understanding self-inductance?

The concept of self-inductance can be difficult to grasp because it involves both the magnetic field and the electric current in a circuit. It is also often confused with mutual inductance, which describes the interaction between two circuits.

3. How does self-inductance affect the behavior of a circuit?

Self-inductance causes a delay in the current flow in a circuit, known as inductive reactance. This can lead to changes in the overall impedance of the circuit and affect its response to changes in current or voltage.

4. How can self-inductance be calculated?

The self-inductance of a circuit can be calculated using the formula L = Φ/I, where L is the self-inductance in Henrys, Φ is the magnetic flux through the circuit, and I is the current flowing through the circuit. It can also be calculated using the number of turns in a coil and the permeability of the material in the circuit.

5. How is self-inductance used in practical applications?

Self-inductance is an important concept in the design of electrical circuits and devices. It is used in transformers, motors, generators, and other devices to control and manipulate the flow of current. It is also used in energy storage applications, such as inductors and chokes, to store energy in the form of a magnetic field.

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